A sad book. Everyone agreed on that.
I re-read The Remains of the Day -also a sad book-before reading Never Let me Go and at first I thought the books were not at all similar. But thinking more about the main characters and their "place in life", their dedication and resignation to it, I realised that the attitudes of the products of Hailsham were in many ways like the self abnegating dedication and resignation of the butler of Darlington Hall who was of such great service to his various masters.
It is not surprising to me that people can be socialised in this way. I see it every day. In myself even. People can be moulded by society's expectations to do thing that are not at all in their self interest, or to do things that at another time and place they would never guess they would be capable of doing. Think of slave traders, or Nazi Germany, or suicide bombers. People have also been encouraged by society to do what we (at least sometimes) think of as good or helpful things in a self sacrificing way. I think of nuns, missionaries, volunteers of all kinds, firemen, doctors, people like Wilberforce, and yes, even soldiers. So the idea of a donor class you might say, a donor cult of parentless clones, is not so outlandish. Not to be wished for but not beyond the imagination.
In Never Let Me Go Ishiguro doesn't shed very much light on the society that raised and used the donor clan he created in his mind's eye. That is left to our imagination. What would it be like? Would it be hideous? Perhaps only in foresight or hindsight. If you were raised in it of for it it would probably seem quite natural and ordinary. The ability to recognise evil when you are part and parcel of it is given I think to few of us. Ishiguro seems to have the gift.